Effects of plant growth regulators on the plant height and quantitative properties of Narcissus tazetta

The effects of flurprimidol, paclobutrazol, and ethephon treatment as soil drench on plant height and quantitative and other properties of native narcissus (Narcissus tazetta L.) plants grown in pots were investigated. When the plants were 7?10 cm tall, flurprimidol and paclobutrazol at 0, 1, and 2 mg/pot and ethephon at 0, 37.5, and 75 mg/pot were applied as soil drenches. The effects of plant growth retardant treatments on plant height, leaf length, time of flowering, number of flowers, and flower life were determined. In addition, quantitative measurements (leaf area ratio, specific leaf area, leaf thickness, leaf weight ratio, and stem weight ratio) were analyzed in native narcissus. When narcissus grown in pots in the greenhouse reached the sale stage, the plants were taken to the laboratory at 20 °C to evaluate the postproduction life and quality of pot plants. Flurprimidol, paclobutrazol, and ethephon shortened plant height. The shortest plant height was obtained from 2 mg/pot paclobutrazol; plant height was 5.42 cm, 65% shorter than the untreated controls. Chemical applications also shortened leaf length. The shortest leaf length (13.25 cm) was obtained from the 2 mg/pot paclobutrazol treatment. The chemical treatment decreased the leaf area ratio and specific leaf area, but increased the leaf thickness and leaf weight ratio compared to the control plants. The effects of treatments on plant height continued in laboratory (home-office) conditions after production. The shortest plant height (9.5 cm) was obtained from the 2 mg/pot paclobutrazol treatment, whereas the height of untreated control plants was 24.25 cm during the postproduction life of pot plants.